This application is national phase of PCT/US2010/025078 filed Feb. 23, 2010, and claims priority under 35 U.S.C. §119 (e) of U.S. provisional application serial no. 61/165,203 filed Mar. 31, 2009.
1. Field of the Disclosure
The present disclosure pertains to a specimen holder for tensile or materials testing, which is mounted directly in the grip of the testing device.
2. Description of the Prior Art
In materials testing, the specimen or testing sample is typically gripped and then pulled or compressed in order to measure the material properties of the specimen. The gripping mechanism can be of several types, including the automatic side-action grip, which can be pneumatic or hydraulic. Typically, the user holds the ends of the specimen between the jaws of the grip and then actuates a switch, typically by the user's hand or foot, to cause the jaws to come together and to grip the specimen. The closing of the jaws is often fast and with enough force that, should the user's fingertips be between the jaws, the user can receive a severe pinch injury. This hazard increases as the jaw face opening increases because this allows more space for a user to insert a finger between the jaws. Industry practice with respect to grips with large jaw face openings is to slow the grip closing speed enough to allow sufficient time for the user to withdraw the finger. However, the slowing of the speed of the jaw face slows the productivity of the user.
It can therefore be difficult to place the specimen or testing sample into position accurately, while maintaining both safety and high work volume.